A display device may include the following elements: a touch screen unit (or touch-sensing unit) operating with a preset touch driving frequency; a display unit operating with a display driving frequency corresponding to a driving control signal; a noise analyzer determining a frequency band of a panel noise based on a feedback signal provided from the display unit, wherein the panel noise is caused by operation of the display unit; and a driving frequency controller controlling the display driving frequency such that the frequency band of the panel noise avoids the touch driving frequency.